I found GIMX while trying to research ways to build a frankenpad without having to cut a dualshock 4 apart. My intention with using this is to allow someone to plug a dualshock 4 controller in to a USB device that adds arcade buttons in place of the buttons on the right of the pad (including shoulder and options button). I've built boxes using a PS1 controller by cutting it apart and soldering directly to the PCB, but I want a plug-and-play solution and am hoping I can use this.

So here are my questions that will ultimately decide if I go through with this or not:

1. Can I use the dualshock 4 at the same time as the other controller connected to the Pi/PC?
2. Using a Pi as the computer, is it possible to just connect arcade buttons to the GPIO on the Pi without needing to plug in a second controller?